The present invention relates to improvements in machine safety equipment, and, in one particular aspect, to novel and improved mechanical arrangements of low-cost and uncomplicated construction which operate efficiently and reliably to block the striking zone of a drop hammer or the like intermittently against access by personnel during critical intervals while the machine produces its forming strokes.
Safety of personnel in the workplace is of course of great private and public concern, and responsible business has evolved and introduced such protective contrivances as stationary enclosures, movable guards, operator restraints, and fluid-braking and electro-optical disabling systems, for machinery having potentially-hazardous machanisms to which required human operators might become exposed under some conditions. In certain types of equipment, such as a drop-hammer machine wherein the rapid gravitational fall of a massive weight nevertheless entails enough of a finite time to admit of the theoretical possibility that its operator might somehow find access to the striking zone, even strict preventive measures designed to keep both of the operator's hands occupied in the triggering may not afford an approvable degree of security. None of the aforementioned known protective equipment is well suited to the task of assuring that the latter possibility will be foreclosed, because stationary enclosures would not allow essential loading and unloading by the operator, and dynamic guards forcefully thrown down with the rapidly-moving weight could themselves be hazardous, and fluid-braking and electro-optical systems could be ineffective once the short free fall of a massive hammer is under way. Accordingly, the present teachings are aimed at refining the safety characteristics of drop hammers, and the like, by way of reliable, inexpensively-fashioned, and fool-proof safety guards.